Know Your Environment. Protect Your Health.

Selenium

Ventura County Waterworks District No. 19 - Somis

Selenium is an essential element in diets. But too much selenium can decrease thyroid hormone production and cause hair loss, skin lesions and brittle fingernails.

 

18

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND30ND
2019ND30ND
2020ND30ND
2021ND30ND
2022ND30ND
20235.67 ppb31ND - 17.0 ppb

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 30 ppb

The EWG Health Guideline of 30 ppb for selenium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against hair loss and nail damage.

EPA Maximum Contaminant
Level (MCL): 50 ppb

The legal limit for selenium, established in 1991, was based on human epidemiological studies of populations exposed to naturally occurring selenium in drinking water. This limit does not include any additional consideration of children’s health.

ppb = parts per billion

All test results

Date Lab ID Result
2018-08-01CA5610015_007_007-201808011337ND
2018-08-01CA5610015_002_002-201808011404ND
2018-08-14CA5610015_001_001-201808141147ND
2019-08-07CA5610015_002_002-201908071345ND
2019-08-07CA5610015_001_001-201908071409ND
2019-08-07CA5610015_007_007-201908071317ND
2020-08-03CA5610015_007_007-202008031556ND
2020-08-04CA5610015_002_002-202008041411ND
2020-08-04CA5610015_001_001-202008041455ND
2021-08-04CA5610015_002_002-202108040830ND
2021-08-04CA5610015_007_007-202108040940ND
2021-08-04CA5610015_001_001-202108041007ND
2022-08-16CA5610015_002_002-202208160933ND
2022-08-17CA5610015_007_007-202208170841ND
2022-08-22CA5610015_001_001-202208221052ND
2023-08-08CA5610015_001_001-202308081445ND
2023-08-08CA5610015_002_002-202308081515ND
2023-08-09CA5610015_007_007-20230809093017.0 ppb